In helicopter logging and mineral exploration operations, it is often necessary to land a helicopter in remote areas that are characterised by uneven or multi-pitched terrain that is at least partially covered with obstacles such as boulders or stumps. Accordingly, helicopter landing pads must typically be constructed at such remote locations before the helicopter logging or mineral exploration operations may begin.
It is standard procedure in the helicopter logging and mining industries to construct helicopter landing pads on-site from timber and other materials that may be available. However, such wooden landing pads are difficult and very time consuming to build. In some cases, it is additionally necessary to first collect and retrieve suitable timber and materials over a large area before the building of the helicopter landing pad may be commenced. Significant quantities of timber and materials may be required, since (depending upon the terrain) a wooden landing pad may have to be tiered in several stages in order to allow for proper clearance for the helicopter rotor. Owing to the variability in timber supplies and other materials suitable for the construction of a wooden helicopter landing pad that one may find at any given remote location, wooden landing pads are of non-uniform construction; this leads to an increased likelihood that a given wooden landing pad may be insufficiently strongly constructed and may collapse.
Previously known portable helicopter landing pads have been proposed for use in the helicopter logging and mining industries and in other operations where it may be necessary to land a helicopter on uneven or multi-pitched terrain covered with obstacles, but have been found to be unsuitable for use in such rugged terrain due primarily to their cost, complexity, and/or poor ground clearance. In U.S. Pat. No. 3,489,380, Vanderlip discloses a portable helicopter landing pad that is designed to permit the landing of troops and supplies in densely foliated areas, but that must be set upon a relatively level clearing if one is to be able to land the helicopter itself upon it. Soloy, in U.S. Pat. No. 4,116,408, discloses a portable helicopter landing pad having a folding deck, which must be folded before the landing pad may be transported by a helicopter. Telescopically extensible legs are provided for in the Soloy pad in order that it may be set upon non-level ground; however, since a folding deck is more susceptible to unwanted collapse, the foldable deck structure requires the use of multiple braces between the legs in a configuration that significantly interferes with ground clearance, thereby rendering the Soloy pad unsuitable for use in rugged terrain. In addition, since it is often advantageous in helicopter logging and mining operations to quickly and repeatedly relocate a portable helicopter landing pad (as the worksite progresses), the requirement that the Soloy pad be folded before it may be transported limits its utility in such operations.